Question

What is a unit rate?

Answer 1

It’s a expression of a rate in a quantity of one.

Answer 2

Unit rate is the cost of a unit of an item.
For example
If I wanted to get a 12 oz soda, the unit would be 1 oz.

If the soda costs $2.50
I'd have to divide by the total amount of ounces there are.

The unit would be about 20 cents for one ounce.